Virus gene turns gypsy mothcaterpillars into climbersScientists have discovered a genethat baculoviruses use to hijackgypsy moth caterpillars’ brains.When infected with the virus, thecaterpillars become climbers, scal-ing the tree on which they live. Atthe top, the caterpillars die, liquefyand rain down viruses on othergypsy moths. Now researchersat Pennsylvania State Universityin University Park and colleagueshave discovered that a baculovirusgene called egt makes the cater-pillars seek the heights. Viruseslacking the gene still kill, but thecaterpillars stay down at the baseof the tree, the researchers reportin the Sept. 9 Science. The egtgene produces an enzyme thatinactivates one of the caterpillar’smolting hormones and leads toclimbing. — Tina Hesman Saey

Corticosterone

(nanograms/milliliter)

Bacteria ease stress Mice forced to
swim in a tank get stressed, but a diet that
includes a bacterium called Lactobacillus
rhamnosus lowers levels of a stress hormone.

Stress hormone levels

300

Comparison mice
under stress

200

Bacteria-fed mice
under stress

Endangered stem cellsReprogrammed stem cells fromtwo of the world’s most endan-gered species may help bring themback from the brink of extinction.Using frozen adult skin cells froman endangered primate called adrill and from a northern whiterhinoceros, scientists coaxedthe cells into an embryonic stemcell–like state. The stem cells mayone day be used to create eggsand sperm for breeding programs.It took many failures before theresearchers succeeded in makingthe cells from a male drill namedLoon and a female rhino namedFatu, the researchers from UC SanDiego, the Scripps Research Insti-tute and the San Diego Zoo reportonline September 4 in NatureMethods. — Tina Hesman Saey